If you can PM me the mesh that was crashing I’d appreciate it. Even a plane without thickness should still be fine.
Can you PM me the mesh?
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I can’t wait to test this out, very useful feature.
The screenshot you posted is the Default setting. You have to change the property, CollisionFidelity, to PreciseConvexDecomposition
PS: I would advise NOT using this mesh as your collision mesh for wheels. This is going to be prohibitively expensive for the physics engine.
A Cylinder would be much better!
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This is so helpful, now I don’t need to resort to making a custom hitbox most of the time with a OBJ Collision Gen plugin which would probably be more laggy then this.
Do you mean envelop my wheel with a cylinder, so the cylinder is the only thing touching the ground? Or removing the mesh and use a cylinder instead?
Is there a way to measure how expensive my mesh is for the physics engine? I would like to know the difference my mesh and a cylinder.
Make the mesh CanCollide false, and use a Cylinder.
Easiest way to compare is to create N of your mesh and stack them in a few columns together, and do the same thing in a different file for Cylinders.
You can then use Using MicroProfiler | Documentation - Roblox Creator Hub to look for “stepContacts” and see how much longer each step takes in both the tests. Make sure to compare an individual step to individual step.
Is the collision expense proportional to the amount of collision cells it makes?
Default:
Precise:
In this case I precise is cheaper as
doesn’t rule against the possibility it can’t be.
What if I had just a bunch of blocks in place of these cells? Would it actually be easier to simulate that and less performance taxing to just weld a hollow tube of blocks together? And if not, is there ever a ball park answer to when n number cells is superior to n number conjoined parts?
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Hello!
This mesh crashes my Studio when changing it to PreciseConvex.
rbxassetid://4333028498
Note: This is from a free model, and it is really detailed. I wanted to test PreciseConvex with detailed meshes.
Thanks in advance,
Meaxis
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You’re not alone on this one. I tried to do this on my PC and use PreciseConvexDecomposition, and I can confirm that it crashes Studio.
I can finally stand on my F7’s nose without floating! I love this update!
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Will this become usable with outputs of real time csg?
doesn’t work perfectly for me
there is one way to make collisions perfect,
duplicate the union, parent it to the union and separate it.
make the parts transparency = 1 and the union cancollide = false
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This is a post that is on the devforums.
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Just a question about and not about the feature… How do you display these collisions on studio ? I still can’t find it, and I want to see where is the collision glitch on my model so I can correct the mesh…
File>Studio Settings>Physics>Show Decomposition Geometry (1 up from bottom)
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This is an amazing new feature. Better unions and all. Great work Roblox! Keep up the good work! 
You can also use CloneTrooper’s plugin for easier access to it
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Forgot to mention, wrote an article about how this works for those curious. Not too technical, lots of pictures.
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Heads up to others who come here searching like I did - this setting is now located here:
(File → Studio Settings → Studio → Visualization → Show Decomposition Geometry)
Thanks Roblox devs for adding this feature! I’m hoping it enhances my users’ gameplay experience. They love doing parkour on my game’s meshes.
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